Self-locking sash balance



May 14, 1957 G. B. HAAS SELF-LOCKING SASH BALANCE 3 Sheets-Sheet 1 Filed Nov. 29, 1954 INVENTOR.

' B. i l 461$ W iFIIw. v

x i ll Ila" III 1 pm mu y 14, 1957 G. B. HAAS 2,791,795

SELF-LOCKING sAsH BALANCE Filed Nov. 29, 1954 3 Sheets-Sheet 2 y 14, 1957 G. B. HAAS 2,791,795

SELF-LOCKING SASH BALANCE Filed Nov. 29, l95 4 3 Shee ts-Sheet 3 /02 [04 IN VEN TOR. m4 m0 e Iii/ems 10o j @QIZWVZW SELF-LOCKING SASI-I BALANCE Glenn B. Haas, Oak Harbor, Ohio, assignor to For-metal, Inc., Oak Harbor, Ohio, a corporation of Ohio Application November 29, 1954, Serial No. 471,760

Claims. (Cl. 16-197) This invention relates to sash balances and, in particular, to sash balances for removable double-hung sliding sash windows.

One object of this invention is to provide a sash balance for removable double-hung sliding sash windows wherein the sash balance is automatically locked in position at the location at which the sash is removed, thereby retaining the balancing spring in full tension as well as temporarily securing the contact member at the position in which the sash was removed, so that when the sash is replaced in its original position, the sash balance is automatically unlocked and the tension of the balancing spring immediately reapplied to the sash to balance its weight.

Another object is to provide a self-locking sash balance for removable sash windows as set forth in the preceding object, wherein the balancing device is mounted within the sash guide and wherein the locking device for the balancing spring engages the interior of the sash guide and thereby avoids any scratching, denting or other damage to the exterior of the sash guide, as occasionally occurs in other self-locking sash balances.

Another object is to provide a self-locking sash balance for removable sash windows, as set forth in the preceding objects, wherein the sash balancing spring is connected at its lower end to a locking assembly including a pivoted detent or locking arm which is urged normally into locking engagement with the interior of the sash guide but which is swung out of engagement therewith by a tripping lever, a portion of which projects beyond the sash guide into the path of travel of the sash for actuation thereby. 4

Other objects and advantages of the invention will become apparent during the course of the following description of the accompanying drawings, wherein:

Figure 1 is a vertical section in a plane parallel to the window pane, of a self-locking sash balancing device for removable double-hung sash windows, according to one form of the invention, with the major parts thereof shown in side elevation in their unlocked position, and with the lower corner of the sash shown in section;

Figure 2 is a vertical section at right angles to the plane of the section of Figure 1, taken along the zigzag nited States PatentO line 2-2 therein, showing certain of the parts in front elevation;

Figure 3 is a horizontal section taken along the line 3-3 in Figure 1, through the self-locking sash balancing device, sash and sash guides, showing the yieldinglymounted sash guide which permits removalof the sash;

Figure 4 is an enlarged fragmentary view of the lowerlefthand corner of Figure 1, showing the parts of the locking device in more detail, in the unlocked position thereof; I a

Figure 5 is a view similar to Figure 4, but showing the parts of the locking device in the locked position thereof, with the sash temporarily removed, taken along the line 5-5 in Figure 7;

Figure 6 is a front elevation of the assembly shown in Figure 5, looking from the right-hand side thereof;

, 2,791,795 Patented May 14, 1957 Figure 7 is a cross-section taken along the line 7-7 in Figure 5;

Figure 8 is a cross-section taken along the line 8-8 in Figure 5;

Figure 9 is a side elevation of the lock carrier;

Figure 10 is a front elevation of the lock carrier of Figure 9, looking from the right-hand side thereof;

Figure 11 is a top plan view of the locking member, removed from the locking device;

Figure 12 is a side elevation of the locking member shown in Figure 11;

Figure 13 is a perspective view of the lock tripping lever, removed from the locking device; and

Figure 14 is a perspective view of the locking member spring, removed from the locking device.

Referring to the drawings in detail, Figure 1 shows a window frame, generally designated 10, having recesses 12 and 14 in the opposite sides thereof (Figure 3) for receiving stationary and yieldingly movable elongated hollow metallic sash guides 16 and 18-20, respectively, slidably receiving the correspondingly ribbed side rails 21 of the upper and lower sashes 22 and 24 respectively of a double-hung sash window, generally designated 26, having window panes 27 and 29 respectively therein. The movable sash guides 18 and 20 are formed of rolled sheet metal of roughly channel-shaped cross-section, the details of which are beyond the scope of the present invention. The movable sash guides 18 and 20, for the purposes of the present invention, may be said to possess sash guide grooves or channels 28 apertured at intervals to receive cups 30 which in turn are centrally apertured to receive stop screws 32 seated in the window frame 10. Conical coil springs 34 encircle the cups 30 and engage the movable sash guides 18 and 20 to urge them outward against the sides of their respective upper or lower window sash 22 or 24, as the case may be.

The stationary sash guide 16, mounted in the recess 12, is of double width accommodating both the upper and lower sashes 22 and 24 in separate spaced guide grooves or channels 36 (Figure 3) with central slots 38 therein leading into the spring chamber 40 of an elongated boxshaped spring housing portion 42 having side walls 41 and a rearward wall 43. The latter is preferably integral with the front portion 44 of the stationary sash guide 16 containing the sash guide channels 36, and has partition walls 45 separating it therefrom on opposite sides of each slot 38, the partition walls 45 having inner contact surfaces 47. The front portion 44 contains a parting strip portion 46, also preferably integral with the remainder of the front 44 and drilled at intervals to receive screws 48 by which the stationary sash guide 16 is anchored to the window frame 10.

Each spring housing 42 at its upper end is drilled as at 50 and 52 to receive a spring anchorage pin 54 to which the hooked upper end 56 of the elongated tension balancing spring 58 is fixedly secured. The lower hooked end 60 of the balancing spring 58 (Figures 1 and 4) is hooked into a hole 62 in the upper end of an approximately L- shaped lock carrier, generally designated 64, forming the support for the sash balance locking device, generally designated 65. The lock carrier 64 is in the form of a plate 66, preferably of metal, having a vertical bar portion 68 with a rectangular notch 70 separating it from a horizontal bar portion 72 (Figures 9 and 10) which projects laterally beyond the vertical bar portion 68. The plate 66 near its upper and lower ends is drilled with holes 74 and 76 respectively (Figure 10) intersecting the front and rear edges 78 and 80 thereof to receive short transverse pins 82 and 84 of plastic or other suitable material, the pins 82 and 84 being of cylindrical form projecting slightly beyond the edges 78 and 80 so as to engage the front and rear walls of the spring housing 42. The

plate 66rearwardly of the notch 70 near the lower corner thereof is provided with a hole 86 and' the horizontal bar portion 72 immediately below the notch 70 is likewise provided with a hole 88.

Pivotally mounted upon a transverse pin 99 seated in the hole 86 is a U-shaped lock-ing member or deteut 92 (Figure 11), the ends of the pin 90' being received in aligned holes 94 on opposite sidesof a central notch 96 extending inwardly from the rearward edge thereof. The notch 96 is formed with a width slightly greater than the thickness of the plate 68, so as to receive the latter and swing freely relatively thereto. The forward portion of the locking detent 92 is provided with a pair of laterally-spaced holes 98 which receive the bentilower ends 100 of a double-armed spring 102 (Figure 14), thelopposite arms 104 of which lie, on opposite sides of the plate 68 and are interconnected by a bridge portion 186. The spring 102 and the locking detent 92thus-project into the notch 70 of theplate 68 with the bridge portion. 166 engaging the rearward edge of the notch 70 (Figure 4). The detent 92 has a relatively sharp forward edge portion 108 which is adapted to swing into locking engagement with the inside surfaces 47of the partition walls 45.

Mounted in the transverse hole 88 in the plate 66 is a pivot pin 110 (Figure 4) upon which a locktripping lever 112 is pivotally mounted (Figure 13). The lock tripping lever 112 is of U-shaped or channel-shaped cross-section with aligned holes 114 in its opposite side Walls 116 receiving the pivot pin 119. The connecting portion or web 118 terminates at the holes 114 and forms the forward arm of 'the lever 112. The latter is provided with a pair of rearward arms 120 with upwardly and rearwardly inclined upper edges 122 terminating in contact points 124 which engage the lower surface 126 of the locking detent 92. From Figure 4 it will be seen that the connecting or web portion 118 of the tripping lever 112 overlies the horizontal bar portion 72 of the plate 66 and engages the upper edge 128 thereof in the balancing or unlocked position of the locking device 65, and swings upward away from it in the locked position thereof (Figure The horizontal bar portion 72 of the plate 66 and the web portion 118 of the tripping lever112 project through their respective slots 38 into the path of travel of the sash side rail 21, which at its lower end is provided with a notch or recess 130 (Figures 1 and 4) with an abutment surface 132 at the upper end thereof.

In the operation of the invention, let it be assumed that the lower, sash 240i? the double-hung window 26 is to be removedffor cleaning orother purposes and has been pulled downward almost to its lowermost position (Figures 1; 2 and 4) so that the tension balancing spring 58 is almost fully extended and the locking device 65 is near the lower end of its path of travel. in this position, the abutment surface 132 of the recess 13! at the. lower corner of the side rail 21 of therlower sash 24 is in engagement with the web portion 118 of the lock tripping lever 112 and has pushed it downward against the upper edge 128 of the horizontal bar portion 72 of the plate 66 (Figures 1 and 4). In this position of the lock tripping lever 112, the contact points 124 on the upper ends of the rear arms 120 haveswung upward around the pivot pin 110 and by their engagement with the lower surface 126 of the locking detent 92 have pushed the latter upward against theurge of the double-armed spring 102, swinging the locking edge S rearwardly away from and out of engagement with the inner surfaces 47of the partition walls 45 on opposite sides of the centralslot 38 through which the lever 112 and horizontal bar portion 72 project (Figure 4).

To remove the-sash 24, the operator grasps it and pushes it sidewise to the right (Figure 3 thereby pushing the movable sash guide 20 to the right and compressing its springs 30. In this manner, the left-hand side rail 21 which has been slidably received in the channel 36 of. the stationary sash guide 16 is moved out 1of.:this channel 36 so that it can be swung in a direction perpendicular to the plane of the window pane 29. The sash 24, thus freed from engagement with the stationary guide channel 36, may be pulled outward to detach its right-hand side rail 21 from the guide channel 28 of the movable sash guide 20 (Figure 3) so as to completely remove the sash 24 from the window frame 10.

The instant the side rail 21 is withdrawn from the guide channel 36 of the stationary sash guide 16, its abutment portion 132 slides off the web 118- of the lock tripping lever 1'12, freeing the latter. Under the influence of the double-armed spring 102, the locking member or detent 92 is then swung downward around its pivot pin 90, bringing its locking edge 108 into gripping engagement with the inner surfaces 47 of the partition walls 45 on opposite sides of the central slot 38.

At the same time,- the downward swin ging'of the locking detent 92 into its locking position causes the upper and lower pins 82 and 84 to swing into engagement with the forward or partition walls 45 and rearward wall 43 (Figures 5; 7 and 8), firmly locking the plate 66 in its attained position and temporarily preventing the balancing spring-58 from pulling it upward until the sash is reinserted; Meanwhile, the downwardswinging of the looking detent 92 under the influence of the double-armed spring 102 rocks the lock tripping lever 112 in a counterclockwise direction-around'its pivot pin by the engagement of'the-lower surface 126'with the contact points 124, causingtheweb portion'118 of the lever 112 to swing upward away from the upper edge 128 of the horizontal bar portion'72 of the plate 66, ready for reinsertion of the sash 24 and engagement by the abutment portion 132 of the siderail 21 thereof.

The sash 24 is reinstalled by placing its left hand side rail 21 in its respective guide channel 28 of the movable sash guide 20, pushing the latter inward to the right (Figure 3) todisplace it sufliciently far to enable the lefthand side rail 21 to re=enter its respective guide channel 36in the stationary sash guide 16. Assuming that the sash '24 has been reinstalled in this manner, in a position raised above the projecting horizontal bar portion 72 and tripping lever 112, the sash'24, which has been urged into the-guidechannel 36 'by the movable sash guide'springs 30; is-slid downward by the-operator until the abutment surface 132 at the upper end of the notch 130 re-engages the web-portion 118 at the outer end of the lock tripping lever 112, swinging-it downward against the upper edge 128 'of the horizontal bar portion 72 of the plate 66 from the-position of-FigureS 'into'the position of Figure 4. This action; in swinging'the tripping'lever 112 clockwise aroundits pivot-pin-lltl, causes the upwardly-swinging contact points 124 on the rearward-arms thereof to engage the bottom surface 126- of the locking detent 92 and swing the contact edge 108'thereof upward out of engagement with the inner-surfaces 47 of the partition walls 45 on opposite sides of the central slot 38.

This action releases the locking device 65 from'engagement withthe spring housing 42, freeing the balancing spring 58-so that it immediately exerts its balancing pull upon the sash 24 =through the contact of the locking device 65 with the abutment surface 132 at the upper end of 'thenotch-134. In this manner, the locking device 65 is maintained inan. inoperative position or status so long asthesash 24 (or the corresponding upper sash 22) is in its installed position. The locking .device 65 thus comes into operationautomatically to lock the tensionin g spring 58-and itself tov thespring housing 42 of the stationary sash:,guide:16:whenever thev sash 22 or 24 is' removed from the window frame It? for cleaning or other purposes.

What-I :claim is:

1. Aresilient sash balancefor removable sliding sash windows which is automatically locked 'in its tensioned condition in response to sash removal at a t given location and:automaticallyareleaseddn response to sash replacementandretumto :said: given location, said-sash balance comprising an elongated housing adapted to be secured to the window frame and having an elongated chamber therein, said housing having elongated longitudinallyextending wall surrounding said chamber and having an elongated opening therein disposed adjacent the sash, an elongated resilient sash balancing element disposed in said housing and anchored thereto at one end, a locking member carrier connected to the other end of said resilient element, a locking member pivotally mounted on said carrier and having a contact portion thereon swingable into and out of locking engagement with the inner surface of said wall, means normally urging said locking member into locking engagement with said inner surface of said wall, and a tripping device movable relatively to said locking member and movably mounted on said carrier with a portion thereof projecting through said opening into the path of travel of said sash for engagement thereby, said tripping device having an actuating portion movable into unlocking engagement with said locking member in response to the engagement of said sash with said projecting portion.

2. A resilient sash balance for removable sliding sash windows which is automatically locked in its tensioned condition in response to sash removal at a given location and automatically released in response to sash replacement and return to said given location, said sash balance comprising an elongated housing adapted to be secured to the window frame and having an elongated chamber therein, said housing having an elongated longitudinallyextending wall surrounding said chamber and having an elongated opening therein disposed adjacent the sash, an elongated resilient sash balancing element disposed in said housing and anchored thereto at one end, a locking member carrier connected to the other end of said resilient element, a locking member pivotally mounted on said carrier and having a contact portion thereon swingable into and out of locking engagement with the inner surface of said wall, means normally urging said locking member into locking engagement with said inner surface of said wall, and a tripping device movable relatively to said locking member and movably mounted on said carrier with a portion thereof projecting through said opening into the path of travel of said sash for engagement thereby, said tripping device having an actuating portion movable into unlocking engagement with said locking member in response to the engagement of said sash with said projecting portion, said carrier comprising an elongated member mounted within said chamber, said elongated member having a transversely-disposed contact element secured thereto near one end thereof and projecting therefrom into engagement with said inner surface of said wall.

3. A resilient sash balance for removable sliding sash windows which is automatically locked in its tensioned condition in response to sash removal at a given location and automatically released in response to sash replacement and return to said given location, said sash balance comprising an elongated housing adapted to be secured to the window frame and having an elongated chamber therein, said housing having an elongated longitudinallyextending wall surrounding said chamber and having an elongated opening therein disposed adjacent the sash, an elongated resilient sash balancing element disposed in said housing and anchored thereto at one end, a locking member carrier connected to the other end of said resilient element, a locking member pivotally mounted on said carrier and having a contact portion thereon swingable into and out of locking engagement with the inner surface of said wall, means normally urging said locking member into locking engagement wtih said inner surface of said wall, and a tripping device movable relatively to said locking member and movably mounted on said carrier with a portion thereof projecting through said opening into the path of travel of said sash for engagement thereby, said tripping device having an actuating portion movable into unlocking engagement with said locking member in response to the engagement of said sash with said projecting portion, said carrier comprising an elongated member mounted within said chamber, said elongated member having a pair of transversely-disposed contact elements secured thereto in longitudinallyspaced relationship and projecting therefrom into engagement with oppositelydisposed portions of said inner surfiace of said wall.

4. A resilient sash balance for removable sliding sash windows which is automatically locked in its tensioned condition in response to sash removal at a given location and automatically released in response to sash replacement and return to said given location, said sash balance comprising an elongated housing adapted to be secured to the window frame and having an elongated chamber therein, said housing having an elongated longitudinallyextending wall surrounding said chamber and having an elongated opening therein disposed adjacent the sash, an elongated resilient sash balancing element disposed in said housing and anchored thereto at one end, a locking member carrier connected to the other end of said resilient element, a locking member pivotally mounted on said carrier and having a contact portion thereon swingable into and out of locking engagement with the inner surface of said well, means normally urging said locking member into locking engagement with said inner surface of said Wall, and a tripping device movable relatively to said locking member and movably mounted on said carrier with a portion thereof projecting through said opening into the path of travel of said sash for engagement thereby, said tripping device having an actuating portion movable into unlocking engagement with said locking member in response to the engagement of said sash with said projecting portion, said carrier comprising an elongated plate mounted within said chamber, said elongated plate having a cutaway portion therein, said locking member and said tripping device being mounted adjacent and projecting into said cutaway portion.

5. A resilient sash balance for removable sliding sash windows which is automatically locked in its tensioned condition in response to sash removal at a given location and automatically released in response to sash replacement and return to said given location, said sash balance comprising an elongated housing adapted to be secured to the window frame and having an elongated chamber therein, said housing having an elongated longitudinallyextending wall surrounding said chamber and having an elongated opening therein disposed adjacent the sash, an elongated resilient sash balancing element disposed in said housing and anchored thereto at one end, a locking arm carrier connected to the other end of said resilient element, a locking arm pivotally mounted on said carrier and having a contact portion thereon swingable into and out of locking engagement with the inner surface of said wall, means normally urging said locking arm into locking engagement with said inner surface of said Wall, and a tripping lever movable relatively to said locking arm and pivotally mounted on said carrier with a portion thereof projecting through said opening into the path of travel of said sash for engagement thereby, said tripping lever having an actuating portion movable into unlocking engagement with said locking arm in response to the engagement of said sash with said projecting portion, said carrier comprising an elongated plate mounted within said chamber, said elongated plate having a cutaway portion therein, said locking arm and said tripping lever being mounted adjacent and projecting into said cutaway portion.

References Cited in the file of this patent UNITED STATES PATENTS 2,101,577 Gossen Dec. 7, 1937 2,257,051 Gossen Sept. 23, 1941 FOREIGN PATENTS 4,006 Great Britain Feb. 22, 1908 

